A question about the amp itself? I'm thrown, I must admit. I'll second that question and add my own. How are the pots mounted? Are they directly connected to the circuit board? I believe I asked that before but didn't get an answer. For some reason, that's been in the back of my mind every time I view this thread. In an amp at this price point with these features, I'd expect them to be, frankly, but it would be nice if they weren't. I worry that I'll get it, really like it, and break it. I know they have a good track record, but I just have a hard time feeling as confident in the lightweight class D stuff, not because it's class D, necessarily, but because of the way a lot of them are put together. There are a lot of flimsy class A/B amps, too, but they're generally easier to fix.
My overstated concern over that matter aside, there's the matter of getting the head... I locked in a nice price when I ordered mine - not life-changing, but nice. I'd hate to let go of that, and I do think that it has the potential to be a King of the Hill micro in its class, but August? I'm not sure. We'll see. I have a Markbass F500 and a Kustom KXB 500 - both capable heads, but both limited to maybe 300 Watts at 8 Ohms. The Peavey was to challenge one or both for their berths.
Ulf, if you need a head, it absolutely makes sense not to wait, especially given that delivery estimates have proven unreliable. Personally, I think either head you mentioned would be fine. Purely from a sound perspective, I'd get the RBII. Plus, should you decide you want the Peavey (or whatever) later, you should be able to move that head pretty easily for what you paid or close to it.